A high power low ripple high dynamic performance DC power supply based on thyristor converter and active filter

Magnets of accelerators etc. require DC power supplies to have high power, extremely low ripple (10^-4-10^-5) and high dynamic following performance without delay. A new scheme based on a thyristor converter (THC) and a paralleled IGBT DC active filter (DAF) is proposed. It is easy to realized high power, low capacity of the active filter and regenerating field energy. Two kinds of control systems: harmonic voltage control based (HVCS) and harmonic current control based (HCCS) are investigated. The key of the DAF are how to measure harmonic signal and how to minimize the response time of the current loop of the DAF and their new solutions are discussed. The feedforward and feedback compound control systems of the HVCS and HCCS and the achievement method of the first and second differential signals for the feedforward are introduced. The proposed system is verified by simulation and prototype experiment.